Homework9_Functions

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#Function name: generate_random_data
#Use: Create a random generate data using a for loop. 
#Variables required and predate: n_groups=4, n_obs_min=25, n_obs_max=100, mean_min=12, mean_max=40, sd_min=2, sd_max=5
#How it works: Itiate with an empty list to store independent df for each group. Second creacte for loop to generate random parameter for each group base on n_groups.
#Finally combine all dataset in one unique df. 
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generate_random_data <- function(n_groups=4, n_obs_min=25, n_obs_max=100, mean_min=12, mean_max=40, sd_min=2, sd_max=5) {
  group_data <- list()
  for (i in 1:n_groups) {
    n_obs <- sample(n_obs_min:n_obs_max, 1)
    group_mean <- runif(1, mean_min, mean_max)
    group_sd <- runif(1, sd_min, sd_max)
    group_data[[i]] <- data.frame(Group = rep(paste0("Group_", i), n_obs),
                                  Value = rnorm(n_obs, mean = group_mean, sd = group_sd))
  }
  all_data <- do.call(rbind, group_data)
  return(all_data)
}

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#Function Name: calculate_group_stats
#owner:DPR
#Create summary statistic for a data frame of groups and values. (2 colums)
#The two columns will need to be named Value and Group. 
#The function input will only need to be the data frame. 
#The output is a dataframe with the summay stats for each group. 

#-------------------------------------------------------------------------

calculate_group_stats <- function(data) {
  group_stats <- aggregate(Value ~ Group, data = data, FUN = function(x) c(mean = mean(x), median = median(x), sd = sd(x)))
  
  return(group_stats)
}



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